Hole punching die arrangement

ABSTRACT

A PLURALITY OF COOPERATING MALE AND FEMALE HOLE PUNCHING MEMBERS RESPECTIVELY MOUNTED IN UPPER AND LOWER DIE PLATES WITH AN INTERMEDIATE DIE PLATE HELD BY UPPER AND LOWER SETS OF RESILIENT MEANS BETWEEN THE UPPER AND LOWER DIE PLATES. BY ADJUSTING THE RELATIVE FORCES EXERTED BY THE RESILIENT MEANS, DURING A POWER STROKE THE LOWER SET YIELDS FIRST TO ALLOW THE INTERMEDIATE DIE PLATE TO EASE INTO HOLDING ENGAGEMENT WITH THE MATERIAL DURING HOLE PUNCHING OPERATION, AND DURING THE RETURN STROKE THE UPPER SET IS FIRST TO CAUSE WITHDRAWAL OF THE MALE PUNCHING MEMBERS FROM THE MATERIAL WHILE THE MATERIAL IS STILL BEING HELD. AS A CONSEQUENCE, NUMEROUS HOLES ARE EFFECTIVELY PUNCHED HAVING LITTLE OR NO PERIPHERAL BURRS.

Sept. 28, 1971 D, BORELLQ 3,608,413

HOLE PUNCIIING DIE ARRANGEMEN'I' Filed Sept. l1, 1969 nted States Patent @mee Patented Sept. 28, 1971 3,608,413 HOLE PUNCHING DIE ARRANGEMENT Domenic Borello, 142 Nyac Ave., Pelham, N.Y. 10803 Filed Sept. 11, 1969, Ser. No. 857,004 Int. Cl. B26d 7/02, 7/ 06, 7/26 U.S. Cl. 83-133 2 Claims ABSTRACT F 'I'HE DISCLOSURE A plurality of cooperating male and female hole punching members respectively mounted in upper and lower die plates with an intermediate die plate held by upper and lower sets of resilient means between the upper and lower die plates. By adjusting the relative forces exerted by the resilient means, during a power stroke the lower set yields first to allow the intermediate die plate to ease into holding engagement with the material during hole punching operation, and during the return stroke the upper set is first to cause withdrawal of the male punching members from the material while the material is still being held. As a consequence, numerous holes are effectively punched having little or no peripheral burrs.

The present invention relates to the production of perforated metal or the like, and more particularly to an improved arangement of die plates mounting hole-punching tooling and having a noteworthy mode of operation for producing burr-free holes or openings.

The use of an intermediate stripping die plate between the upper and lower die plates which actually mount the cooperating cutting tooling, dies, or punch members is already well known. Typically, this plate is suspended or otherwise supported from the upper plate which mounts the male punch members with a biasing spring interposed between it and the upper die plate. The biasing spring is effective in holding the material following punching operation and during withdrawal or stripping movement of the male punches from the material, but it is not otherwise effective in contributing to efficient hole-punching operation. Among other things, for example, this typical prior art arrangement has no spring or resilient means cushioning the impact of the stripping plate against the material supported on the lower die plate.

Broadly, it is an object of the present invention to provide an improved hole punching die arrangement overcoming the foregoing and other shortcomings of the prior art. Specifically, it is an object to fioat the stripping plate between opposing resilient means and to achieve proper sequential movement of this die plate during the power and return strokes by adjusting the forces exerted by these resilient means.

An arrangement of superposed, punch-mounting die plates demonstrating objects and advantages of the present invention includes cushioning resilient means interposed between an otherwise conventionally downwardly biased stripping plate. The arrangement, however, further includes simple and effective means for regulating the relative forces exerted by the opposing cushioning and biasing means so that the former does not interfere with the holding and stripping function of the stripping die plate which, nevertheless, is effectively eased into material-holding contact against the urgency of the cushioning means.

The improved die arrangement hereof also includes other noteworthy structural features. Among such features is the capability of adjusting the depending position of each of the male punches from the upper die plate. The invention contemplates making the necessary adjustment such that the punches are, at different times, urged through the material. This has been found to minimize stressing of the material.

The above brief description, as well as further objects, features and advantages of the present invention, will be more fully appreciated by reference to the following detailed description of a presently preferred, but nonetheless illustrative embodiment in accordance with the present invention, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a simplified perspective view of a hole punching die arrangement according to the present invention;

FIG. 2 is a side elevational view in section taken along line 2 2 of FIG. 1, illustrating further structural features of the arrangement;

FIG. 3 is similarly a side elevational view, but taken in section along line 3--3 of FIG. l, and illustrating further structural features;

FIGS. 4 and 5 are partial front views illustrating the sequential movements of the die plates of the arrangement during a typical power stroke. More particularly, FIG. 4 illustrates the f irst movement sequence of the material holding and stripping die plate into holding engagement with the material, and FIG. 5 illustrates the second or concluding movement sequence of the male punch-holding die plate closing upon the material and providing holepunching operation; and

FIG. 6 is a partial sectional view further illustrating the material punching operation of the arrangement hereof.

Reference is now made to the drawings, and particularly FIG. 1, wherein there is shown a simplified, perspective illustration of a multiple die plate arrangement, generally designated 10, which is particularly useful in punching plural holes in thin strip material. A material with the punched holes (not shown) which is advantageously produced by the arrangement 10 is that used as the anode and cathode plates for batteries. The mention of this product is not intended as a limitation on the use of the arrangement 10, but inasmuch as battery plates require extensive perforation or the punching of numerous holes, sometimes as many as a hundred, this product readily serves to illustrate the noteworthy production performance of the arrangement 10, all as will be described now in greater detail.

In the simplified perspective view of FIG. l, it is readily noted that arrangement 10 includes three die plates, to wit: a first upper, movable male punch-holding die plate 12, an intermediate or interposed material holding and stripping die plate 14, which is also movable during operation of the arrangement 10', and finally a stationary, lower female punch-holding die plate 16. Within a prescribed operative area of the die plates, as illustrated, for example, by the operative area 18 delineated on the die plate 12, the plates are provided with aligned plural openings, individually and collectively designated 20. Respectively disposed in these openings, all as will be described in greater detail subsequently, are the male punch members 48 in die plate 12, guide members 58 for the male punch members in die plate 114, and finally female punch members 62 in die plate 16. Naturally, the location of the aligned holes 20 determine the location where holes will be punched in material M fed between the two lower die plates 14 and 16. Moreover, in accordance with a noteworthy aspect of the operation of the arrangement 10, during a power stroke or when the die plates close upon the material being punched, the movement of the die plates occurs in two distinct movement sequences. First, die plate 14 closes upon the material being punched which is then in an interposed position between it and die plate 16. Next, die plate 12 is urged through closing movement which results in the male punch members being forced through the securely held material. During reverse or opening movement of the die plates, die plate 12 is the first moved through opening movement to its starting or ready position, such movement occurring while the die plates 14 and 16 are still in holding engagement with the material M that has been punched. Thus this opening movement of die plate 12 results in stripping movement of the male punch members 48 from the perforated material M.

Referring now to FIGS. 2, 3 in conjunction with FIG. l, it will be noted that arrangement 10 includes a pair of spaced-apart guide bars 22 and 24, the lower ends of which extend through and beneath the die plate 16 and,l as best shown in FIG. 2, have movement-limiting flanges 26. The bars 22, 24 are also extended through through bores in the intermediate die plate 14 and, at their opposite ends, are threaded as at 28, and are each threadably engaged to stop members 30 such that the members 30 and flanges 26 define the maximum extent of opening movement of the die plates 12 and 14 relative to the stationary die plate 16.

Normally holding the die plates 12, 14 and 16 in their open positions relative to each other are a first and second set of resilient means respectively having an interposed position between the pair of die plates 12 and 14 and between the pair of die plates 14 and 16. More particularly, the rst set of yieldable resilient means consists of four generally cylindrical compressible plastic members, individually and collectivey designated 32. The description of the operative mounting of one resilient member 32 should suce for all. As best shown in FIG. 3, the lower end of resilient member 32 is seated in an upwardly facing counterbore 32 of the die plate 14 while the upper end thereof is projected into a threaded through bore 36 and seated against a threaded member 38. As generally understood, resilient member 32 has an inherent resistance to compression which is a function of the material of which it is fabricated and, in response to a load placed upon it will exert an equal and opposite force. Also as generally understood, the resistance to compression and corresponding outward urgency of member 32 can be regulated Iby the -load placed upon it and, this in turn, in the illustrated embodiment is a' function of the threaded position of member 38 within the threaded bore 36. That is, upon tightening up of the member 38, member 32 is, of course, compressed, thus building up the resistance of this member to further compression. The significance of the adjusted resistance to compression of the first set of resilient members 32 will become more apparent subsequently in the description.

The second set of resilient means, individually and collectively designated 40, is practically similarly mounted in its interposed position between the die plate 14 and stationary plate 16. In this instance, however, the upper end of each member 40 is seated in a counterbore 42 in the lower surface of the die plate 14 and the lower end is projected into a threaded through bore 44 and seated against a cooperating threaded member 46. From the foregoing description it should therefore be readily apparent that the die plates 12, 14 and 16 are normally maintained in an open relation in their respective ready positions as illustrated in response to the urgency of the resilient members 32 and 40 preparatory to a power stroke during which, as already noted, die plates 12 and 14 are urgedlthrough closing movement upon the die plate 16 and result in the punching of holes through the material M in place between the die plates 14 and 16.

To actually punch holes in the material M, use is made of a plurality of male punch members, individually and collectively designated 48. Each male punch member 48 includes an upper threaded body 50 threadably disposed in a cooperating threaded through bore 52 in the diel plate 12 so that each of the members 48 has a depending operative position from the male punch-holding die plate 12. A threaded member 54 is threaded against'each of the punch bodies 50 to hold the same in place. As readily noticeable in FIG. 3, it is advantageous to have the different male punch members 48 adjusted to different de- 4 pending positions from the die plate 12 so that the punching or cutting ends 56 of these members actually are urged through a punching stroke through the material M at different times. This has been found to minimize the extent of stress created in the material during hole punching operation.

Turning now to the construction of the intermediate or stripping die plate 14, it will be noted that in alignment with each male punch member 48 there is a threaded guide member 58 including a central guide opening 60 through which the male punch is projected during closing movement or a power stroke of the arrangement 10.

The cooperating female punch members, individually and collectively designated 62, are threadably disposed in threaded through bores 64 in the stationary die plate 16, each of the members 62 being held in place by a threaded member 66. Each cooperating pair of members 62, 66 includes an aligned central opening 68 of a size and shape conforming to that of the depending shank of the male punch members 48. This is clearly illustrated in FIG. 6 wherein it is further illustrated that the openings 68 function as exit openings for the material 70 removed from the material M in order to produce the punched holes in the material M. It should also be noted that in a preferred setup of the arrangement 10, that it is desirable to threadably adjust each of the female members 62 so that the upper portion thereof extends slightly above the upper surface 72 of the stationary die plate 16. This slight clearance has been exaggerated in FIG. 6` for purposes of clairity of illustration. It has been found that movement of the material M along the stationary plate 16 thus does not result in Wear of the upper surface 72, but only in wear of the upper portions of the female die members 62. When this wear becomes excessive, it is necessary then merely to replace the members 62 rather than the entire die plate 16.

The operation of the arrangement 10 can readily be understood from FIGS. 2, 4 and 5 to which reference is now made. Preferably, the die plates 12 and 14 are urged through hole punching `movement by the rotation of one or more eccentrics 74 appropriately xedly mounted on a power shaft 76. That is, rwith material M in its proper interposed position between the die plates 14 and 16, the eccentrics 74 are rotated so that the throw thereof is effective in causing movement of movable die plates 12 and 14 in accordance with the movement sequences now to be described. The present invention contemplates that in the setting up of the arrangement 10, the first set of resilient members 32 will have the greater extent of resistance to compression such that when the eccentrics 74 urge die plate 12 through movement, the resilient members 32 resist compression while the second set of resilient means 40 yields to the compressive force being applied by the eccentrics 74. As a consequence, and as best shown in FIG. 4, both the die plates 12 and 14 descend through closing movement 78 with the result that die plate 14 closes upon material M which is in postion upon the stationary die plate 16. This closing movement, however, is cushioned by the resilient means 40. Then, While the material M is being held between the die plates 14 and 16, continued closing movement of the upper die plate 12 results in the male punch members 49 being urged through punching movement through the material M, all as is clearly illustrated in FIGS. 5, 6.

In response to continued rotation of the eccentrics 72, and more particularly'rotation of these members past dead center point, the die plates 14 and 12 are correspondingly are smoothly and effectively withdrawn from the material so as to minimize `burring of the periphery of the holes that were punched in the material M.

Ultimately, the force urgency of each member 32 reaches a point Where it is less than the urgency being exerted by the members 40 such that disengaging movement of the die plate 14 from the material M starts to commence. At this time, however, the male punches 48 are completely Withdrawn from the material M. As a consequence of opening movement 82 of the die plate 14, the material M is released and either can be removed and replaced with another sheet requiring punching or, if in strip form, the next succeeding length portion can be moved into proper position for hole punching.

A latitude of modification, change and substitution is intended in the foregoing disclosure and in some instances some features of the invention will be employed Without a corresponding use of other features.

What is claimed is:

1. A hole punching die arrangement comprising an operative, superposed arrangement of a male punch-holding die plate, a material holding and stripping die plate, and a female punch-holding die plate, movement actuating means operatively arranged to urge said die plates from starting ready positions through closing movement incident to material punching operation and thereafter to release said die plates for opening movement back to said ready positions, and a first and .a second arrangement of yieldable resilient means of unequal resistance to compression respectively having interposed positions between said die plates, said die plates having threaded bores therein in which are accommodated the opposite ends of said resilient means of said first and second arrangement, threaded members threadably adjustable in position in said threaded lbores to correspondingly regulate the extent of resistance to compression of said resilient means, said first resilient means between said male punch-holding die plate and said material holding and stripping die plate having said larger extent of resistance to compression, whereby during said closing movement of said die plates, said second resilient means yields first resulting in holding engagement of said material by said material holding and stripping die plate and during said reverse opening movement of said die plates said first resilient means expands first resulting in stripping movement of said male punchholding die plate relative to said material holding and stripping die plate.

2. A hole punching die arrangement as defined in claim 1 including stop means confining said die plates to a selected extent of opening movement in response to the urgency of said resilient means.

References Cited UNITED STATES PATENTS 1,279,851 9/1918 Dunlap 83-133X 1,613,766 l/1927 Parcher 83-687 1,739,200 12/1929 Zsigmondy 83-143X 2,172,272 9/1939 Booth 83-687 2,355,344 8/1944 Wales 83-690X 2,362,039 11/1944 Whistler et al. 83-685 2,379,271 6/1945 Bechtel 83685X 2,384,708 9/1945 Tauser 83-139X 2,553,615 5/1951 Wales 83--139 3,354,766 11/1967 Daalderop 83-133 FRA-NK T. YosT, Primary Examiner U.S. Cl. X.R. 

